Use Of Parasites To Clarify Residency And Migration Patterns Of Pacific Sardine (Sardinops Sagax) In The California Current

Migration patterns of the northern subpopulation of the Pacific sardine (Sardinops sagax) were examined by using parasites as biological tags. This approach has been employed on marine fish species worldwide, but it had not yet been used to investigate the migratory behavior of this ecologically and commercially valuable species in the California Current. In 2005-2008, 14 taxa of parasites were recovered from 1388 Pacific sardine collected between British Columbia, Canada, and Southern California. The results of multivariate analyses indicate significant differences in parasite communities among all size classes of Pacific sardine caught off Vancouver Island, British Columbia, compared with those caught off Washington and Oregon and regions off California. Significant differences in parasite communities also were identified between size classes of Pacific sardine: <210, 210-219, and >= 220 mm in standard length. Our results support a high degree of residency in all size categories of Pacific sardine off Vancouver Island during the study period, and they indicate that individual sardine behavior is not limited to completing an annual migration between British Columbia or the Pacific Northwest and Southern California. These data indicate that using parasites as biological tags could help clarify annual migration patterns of individual Pacific sardine.